Towards better explosives detectors

October 21, 2010

Over the past decade, Christine Mahoney and a team of scientists at the National Institute of Standards and Technology (NIST) in Maryland have been working to stop the threat of terrorist-based attacks in the form of explosives or explosive-based devices, by providing a sound measurement and standard infrastructure.

"Our program encompasses many different aspects of explosives research, from development of measurement standards for trace explosives detection at airports, to the development and application of new metrology for the direct characterization and identification of these explosives," says Mahoney, who is making a presentation today at the AVS 57th International Symposium & Exhibition, which takes place this week at the Albuquerque Convention Center in New Mexico.

One measurement technique, Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is proving to be critical for identifying and differentiating the various components of explosives. ToF-SIMS is a mass spectrometric-based imaging technique that is able to detect components such as plasticizers, binders, oils, and the explosives themselves. It can potentially be used to differentiate between explosive manufacturers and to reveal an explosive material's country of origin.

Unlike traditional analytical techniques such as gas and liquid chromatography, which can provide a partial analysis of extracted samples, ToF-SIMS and other mass spectrometric imaging techniques allow for the simultaneous and direct characterization of all the components in explosives like C4, including the explosive active components, additives, binders, and contaminants. ToF-SIMS provides rapid identification of both organic and inorganic constituents and their characteristic isotopic abundances with excellent sensitivity. Most importantly, it is well-suited for direct analysis of small explosive particulates collected directly in the field and sent back to the lab.

According to Mahoney, the laboratory technique is sensitive enough to detect bits of explosive material scattered in a fingerprint, making it a potentially powerful forensic tool. "It's a more thorough way of looking at the material," says Mahoney. "We look at everything all at once."

Using ToF-SIMS in combination with other techniques that visualize the crystal structure of the samples, Mahoney identified and differentiated between commercial C4, military C4 from the United States, and C4 from the U.K.

The ultimate goal of the project, though, is not to develop ToF-SIMS as a portable technology to use in the field. Rather, Mahoney is creating a library of precise, standardized reference samples that could be used to test, calibrate, and optimize new technologies for detecting explosives in the field.

"We can really nail down the differences in the chemistries between different kinds of explosives," said Mahoney.

Related Stories

Scientists in Japan have developed a new technique for sensing explosives in luggage and landmines. The paper, published today in the Institute of Physics journal Superconductor Science and Technology describes how radio ...

Airplane passengers and baggage might be screened one day by a machine under development at Lawrence Livermore National Laboratory (LLNL) that can detect explosive, chemical and biological agents all at the same time.

Scientists in Germany are reporting development of a new generation of explosives that is more powerful than TNT and other existing explosives, less apt to detonate accidentally, and produce fewer toxic byproducts. Their ...

A group of researchers in Tennessee and Denmark has discovered a way to sensitively detect explosives based on the physical properties of their vapors. Their technology, which is currently being developed into prototype devices ...

Security personnel need to be able to find explosive materials and persons who have been in contact with them. To aid such searches, the National Institute of Standards and Technology, with support from the Department of ...

Recommended for you

When life on Earth began nearly 4 billion years ago, long before humans, dinosaurs or even the earliest single-celled forms of life roamed, it may have started as a hiccup rather than a roar: small, simple molecular building ...

Using a hybrid silica sol-gel material and self-assembled monolayers of a common fatty acid, researchers have developed a new capacitor dielectric material that provides an electrical energy storage capacity rivaling certain ...

Virginia Commonwealth University and University of Richmond researchers recently teamed up to explore the inner workings of cells and shed light on the 400–600 million years of evolution between humans and early animals ...

(Phys.org)—A team of researchers at the Pennsylvania State University has created a new polymer that is able to store energy at higher temperatures than conventional polymers without breaking down. In their paper published ...